After the Orioles' 4-2 loss to the New York Yankees on Monday, Jimenez has lost both of his first two starts, pitched to a 6.75 ERA and allowed 21 base runners -- including eight walks -- over 10 2/3 innings.
Over his career, Jimenez has a 10-10 record with a 5.02 ERA in April and is 72-67 with a 3.86 ERA after that. Last season, Jimenez was 1-2 with a 7.13 ERA in the season's first month, but he was 12-7 with a 2.72 ERA throughout the rest of the season.
"I think I've been a slow starter," Jimenez said. "The one time that hadn't happened was in 2010, and I think that was because I played winter ball before I got to spring training, so my arm was ready. That's probably why. Sometimes, maybe, it takes a little while for me to put everything together."
Jimenez, 30, struggled mightily early in the 2013 season. He had an 11.25 ERA through his first three starts, including back-to-back games in which he allowed seven earned runs against the Yankees and Boston Red Sox -- the same two teams he faced in his first two starts this year. He also walked eight hitters in those two starts.
In Monday's loss, Jimenez issued five walks and allowed four runs and eight hits with four strikeouts in 4 2/3 innings. After the game, Jimenez said he had a good fastball but struggled to locate his breaking ball.
"I don't really look at him struggling his last two starts," Orioles manager Buck Showalter said Tuesday. "Maybe he has in the past. He had stuff to get through seven or eight innings yesterday. It wasn't like he was throwing the ball all over the place and short-hopping the catcher and hitting the backstop. He was barely missing.
"His first outing was very similar. Mechanically, the same thing that allows him to be deceptive and do some things, sometimes challenges him, but he's been able to get back in sync with it. He got a lot of two-strike counts yesterday. He pitched real effectively and will this year. I'm glad we got him."
Last year, Jimenez rebounded from a rocky first three starts. Over his final 28 starts in 2013, Jimenez allowed more than three earned runs in a start just twice.
"I hear some guys go, 'Well, my numbers will be there at the end of the year,' " Showalter said. "I know Ubaldo doesn't look at it that way. From the positive standpoint, that bodes well if you look at track record. But it's not like he's saying or [pitching coach] Dave [Wallace] is saying this is just something we've got to go through. Grin and bear it. He doesn't. ... I think the best it ahead of him."
Despite being disappointed with the beginning to his season, Jimenez said he's not worried after being able to rebound from some rough opening months to the season in the past.
"There's no doubt about it," Jimenez said. "I don't panic. I want to be there for the team and it's been a tough two games but I've been able to shake it off. I've never given up. I work hard every day and I'm getting ready for my next start. That's one thing I've put in my mind -- that I know if I keep working hard -- things are going to change."